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Mathematical Modeling of the Dynamics of Shoot-Root Interactions and Resource Partitioning in Plant Growth.

Feller C, Favre P, Janka A, Zeeman SC, Gabriel JP, Reinhardt D - PLoS ONE (2015)

Bottom Line: Our main goal was to grasp the dynamic adaptation of shoot:root ratio as a result of changes in light and Pi supply.The results of our study are in agreement with balanced growth hypothesis, suggesting that plants maintain a functional equilibrium between shoot and root activity based on differential growth of these two compartments.Furthermore, our results indicate that resource partitioning can be understood as the emergent property of many local physiological processes in the shoot and the root without explicit partitioning functions.

View Article: PubMed Central - PubMed

Affiliation: Dept. of Mathematics, University of Fribourg, Fribourg, Switzerland.

ABSTRACT
Plants are highly plastic in their potential to adapt to changing environmental conditions. For example, they can selectively promote the relative growth of the root and the shoot in response to limiting supply of mineral nutrients and light, respectively, a phenomenon that is referred to as balanced growth or functional equilibrium. To gain insight into the regulatory network that controls this phenomenon, we took a systems biology approach that combines experimental work with mathematical modeling. We developed a mathematical model representing the activities of the root (nutrient and water uptake) and the shoot (photosynthesis), and their interactions through the exchange of the substrates sugar and phosphate (Pi). The model has been calibrated and validated with two independent experimental data sets obtained with Petunia hybrida. It involves a realistic environment with a day-and-night cycle, which necessitated the introduction of a transitory carbohydrate storage pool and an endogenous clock for coordination of metabolism with the environment. Our main goal was to grasp the dynamic adaptation of shoot:root ratio as a result of changes in light and Pi supply. The results of our study are in agreement with balanced growth hypothesis, suggesting that plants maintain a functional equilibrium between shoot and root activity based on differential growth of these two compartments. Furthermore, our results indicate that resource partitioning can be understood as the emergent property of many local physiological processes in the shoot and the root without explicit partitioning functions. Based on its encouraging predictive power, the model will be further developed as a tool to analyze resource partitioning in shoot and root crops.

No MeSH data available.


Related in: MedlinePlus

Adaptive response of P. hybrida to different light and Pi supply.(A) Effects of light intensity on root fraction. Plants were grown under 450 μmol m-2 s-1 (circles), 191 μmol m-2 s-1 (squares) or 93 μmol m-2 s-1 (triangles). Root fraction was determined between 28 and 78 days after germination. Error bars represent the standard deviations (N = 3). (B) Effects of Pi supply on root fraction in P. hybrida. Plants were grown with 10 μM KH2PO4 (triangles) or with 100 μM KH2PO4 (circles). In two additional treatments, plants were transferred from low to high (open triangles), or from high to low Pi supply (open circles) at 41 days after sowing (arrow). Root fraction is defined as the proportion of root fresh weight divided by the fresh weight of the entire plant. Error bars represent the standard deviations (N = 5).
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pone.0127905.g001: Adaptive response of P. hybrida to different light and Pi supply.(A) Effects of light intensity on root fraction. Plants were grown under 450 μmol m-2 s-1 (circles), 191 μmol m-2 s-1 (squares) or 93 μmol m-2 s-1 (triangles). Root fraction was determined between 28 and 78 days after germination. Error bars represent the standard deviations (N = 3). (B) Effects of Pi supply on root fraction in P. hybrida. Plants were grown with 10 μM KH2PO4 (triangles) or with 100 μM KH2PO4 (circles). In two additional treatments, plants were transferred from low to high (open triangles), or from high to low Pi supply (open circles) at 41 days after sowing (arrow). Root fraction is defined as the proportion of root fresh weight divided by the fresh weight of the entire plant. Error bars represent the standard deviations (N = 5).

Mentions: Experiment 2: To explore the adaptive potential of petunia to Pi supply, plants were grown under a light intensity of 316 μmol m-2s-1 and with a Pi (KH2PO4) supply of 10 μM (experiment 2, treatment A) and 100 μM (experiment 2, treatment B), respectively. In two additional treatments, the nutrient solutions were swapped after 43 days: From 10 μM to 100 μM (experiment 2, treatment C) and from 100 μM to 10 μM KH2PO4 (experiment 2, treatment D; experimental design as in Fig 1).


Mathematical Modeling of the Dynamics of Shoot-Root Interactions and Resource Partitioning in Plant Growth.

Feller C, Favre P, Janka A, Zeeman SC, Gabriel JP, Reinhardt D - PLoS ONE (2015)

Adaptive response of P. hybrida to different light and Pi supply.(A) Effects of light intensity on root fraction. Plants were grown under 450 μmol m-2 s-1 (circles), 191 μmol m-2 s-1 (squares) or 93 μmol m-2 s-1 (triangles). Root fraction was determined between 28 and 78 days after germination. Error bars represent the standard deviations (N = 3). (B) Effects of Pi supply on root fraction in P. hybrida. Plants were grown with 10 μM KH2PO4 (triangles) or with 100 μM KH2PO4 (circles). In two additional treatments, plants were transferred from low to high (open triangles), or from high to low Pi supply (open circles) at 41 days after sowing (arrow). Root fraction is defined as the proportion of root fresh weight divided by the fresh weight of the entire plant. Error bars represent the standard deviations (N = 5).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4495989&req=5

pone.0127905.g001: Adaptive response of P. hybrida to different light and Pi supply.(A) Effects of light intensity on root fraction. Plants were grown under 450 μmol m-2 s-1 (circles), 191 μmol m-2 s-1 (squares) or 93 μmol m-2 s-1 (triangles). Root fraction was determined between 28 and 78 days after germination. Error bars represent the standard deviations (N = 3). (B) Effects of Pi supply on root fraction in P. hybrida. Plants were grown with 10 μM KH2PO4 (triangles) or with 100 μM KH2PO4 (circles). In two additional treatments, plants were transferred from low to high (open triangles), or from high to low Pi supply (open circles) at 41 days after sowing (arrow). Root fraction is defined as the proportion of root fresh weight divided by the fresh weight of the entire plant. Error bars represent the standard deviations (N = 5).
Mentions: Experiment 2: To explore the adaptive potential of petunia to Pi supply, plants were grown under a light intensity of 316 μmol m-2s-1 and with a Pi (KH2PO4) supply of 10 μM (experiment 2, treatment A) and 100 μM (experiment 2, treatment B), respectively. In two additional treatments, the nutrient solutions were swapped after 43 days: From 10 μM to 100 μM (experiment 2, treatment C) and from 100 μM to 10 μM KH2PO4 (experiment 2, treatment D; experimental design as in Fig 1).

Bottom Line: Our main goal was to grasp the dynamic adaptation of shoot:root ratio as a result of changes in light and Pi supply.The results of our study are in agreement with balanced growth hypothesis, suggesting that plants maintain a functional equilibrium between shoot and root activity based on differential growth of these two compartments.Furthermore, our results indicate that resource partitioning can be understood as the emergent property of many local physiological processes in the shoot and the root without explicit partitioning functions.

View Article: PubMed Central - PubMed

Affiliation: Dept. of Mathematics, University of Fribourg, Fribourg, Switzerland.

ABSTRACT
Plants are highly plastic in their potential to adapt to changing environmental conditions. For example, they can selectively promote the relative growth of the root and the shoot in response to limiting supply of mineral nutrients and light, respectively, a phenomenon that is referred to as balanced growth or functional equilibrium. To gain insight into the regulatory network that controls this phenomenon, we took a systems biology approach that combines experimental work with mathematical modeling. We developed a mathematical model representing the activities of the root (nutrient and water uptake) and the shoot (photosynthesis), and their interactions through the exchange of the substrates sugar and phosphate (Pi). The model has been calibrated and validated with two independent experimental data sets obtained with Petunia hybrida. It involves a realistic environment with a day-and-night cycle, which necessitated the introduction of a transitory carbohydrate storage pool and an endogenous clock for coordination of metabolism with the environment. Our main goal was to grasp the dynamic adaptation of shoot:root ratio as a result of changes in light and Pi supply. The results of our study are in agreement with balanced growth hypothesis, suggesting that plants maintain a functional equilibrium between shoot and root activity based on differential growth of these two compartments. Furthermore, our results indicate that resource partitioning can be understood as the emergent property of many local physiological processes in the shoot and the root without explicit partitioning functions. Based on its encouraging predictive power, the model will be further developed as a tool to analyze resource partitioning in shoot and root crops.

No MeSH data available.


Related in: MedlinePlus